Silicon nanomembrane(SiNM)transistors gated by chitosan membrane were fabricated on plastic substrate to mimic synapse behaviors.The device has both a bottom proton gate(BG)and multiple side gates(SG).Electrical transfer properties of BG show hysteresis curves different from those of typical SiO_2 gate dielectric.Synaptic behaviors and functions by linear accumulation and release of protons have been mimicked on this device:excitatory post-synaptic current(EPSC)and paired pulse facilitation behavior of biological synapses were mimicked and the paired-pulse facilitation index could be effectively tuned by the spike interval applied on the BG.Synaptic behaviors and functions,including short-term memory and long-term memory,were also experimentally demonstrated in BG mode.Meanwhile,spiking logic operation and logic modulation were realized in SG mode. Silicon nanomembrane (SiNM) transistors gated by chitosan membrane were fabricated on plastic substrate to mimic synapse behaviors. The device has both a bottom proton gate (BG) and multiple side gates (SG). Electrically transfer properties of BG show hysteresis curves different from those of typical SiO_2 gate dielectric. Synaptic behaviors and functions by linear accumulation and release of protons have been mimicked on this device: excitatory post-synaptic current (EPSC) and paired pulse facilitation behavior of biological synapses were mimicked and the paired-pulse facilitation could be effectively tuned by the spike interval applied on the BG. Synaptic behaviors and functions, including short-term memory and long-term memory, also also experimentally demonstrated in BG mode.Meanwhile, spiking logic operation and logic modulation were realized in SG mode.